Classified by the purpose of playing, expressions by sound in Kabuki fall roughly into the following three categories.

Music and sound effects played behind the Kuromisu (black bamboo curtain) on the Shimote (stage right): this is also called Geza-ongaku. The musicians cannot be seen from audience seats. Music and sound effects appropriate to each scene are played here, assisting the progress of stage performances.

Shosa-ongaku is played on stage, and is directly related to actor's performances. Shosa-ongaku includes the Takemoto narration for Gidayu-kyogen, and the Nagauta, Tokiwazu and Kiyomoto music played as the accompaniment for Shosagoto or Buyo (dance plays).

Ki & Tsuke are distinctive sound expressions that cannot be classified in the above two categories. Two pieces of oak wood cut in square section are used. When the 2 pieces are struck against each other they produce the Ki sound, and when the 2 pieces are struck against a hardwood board they produce the Tsuke sound. Ki and Tsuke are used for different scenes and purposes.